福建厦门微小牛蜱中埃立克体的检测与鉴定

Detection and identification of Ehrlichia sp.in Boophilus microplus ticks from Xiamen of Fujian Province

目的检测福建厦门微小牛蜱携带的埃立克体,进行分类鉴定。方法采用套式PCR方法检测埃立克体,然后对阳性标本中的埃立克体进行16S rRNA全基因序列测定并分析。结果共检测吸血微小牛蜱标本299份,27份阳性,阳性率为9.0%。选择其中的1份阳性样本扩增16S rRNA的全基因序列,全长1458bp,序列对比显示与泰缅边境和越南的埃立克体同源性为99.9%,相差2个碱基;与西藏埃立克体同源性为99.7%,相差4个碱基;与非洲埃立克体同源性为99.6%,相差7个碱基;与中国南方的查菲埃立克体同源性为98.9%,相差17个碱基。结论从福建厦门微小牛蜱中检测到埃立克体,可能是一个埃立克体新的亚种。

Objective To detect and identify the Ehrlichia pathogens from Boophilus microplus ticks collected from Xiamen in Fujian Province. Methods A nested PCR specific for tick-transmitted Ehrlichia sp. was established with 3 pair of primers designed based on the 16S rRNA sequence of Ehrlichia. The 16S rRNA sequence of Ehrlichia in a repre- sentative fragments sample was determined and analyzed. Results 27（9.0%） of 299 B. microplus were detected posi- tive. A representative sample was selected for 16S rRNA gene sequence. A sequenced 1 458 base pairs was obtained. The sequence similarity of the newly detected Fujian Ehrlichia sp. was 99.9 % to that of Ehrlichia sp. EBm52 from the Thai- Myanmar border and Vietnam, 99.8% to that of Ehrlichia sp. from Tibet of China, 99.6~ to Ehrlichia sp. ERm58 from Africa, 98.9% to the E. chaffensis from Southern China. Conclusion This is the first report that Ehrlichia sp. was detected in B. microplus from Fujian. The agent detected in the study is probably a new subspecies.